1. Field of the Invention
The present invention relates to a planting machine embodying a novel arrangement for lifting and carrying planting units, with the weight of the units uniformly and evenly distributed on the machine during an inoperative transportation of the machine, the machine comprising a chassis for carrying the planting units in an operative position and a rolling transportation chassis including lifting means and rotation means for lifting and rotating the chassis carrying the planting units to place the same in an inoperative position.
More particularly, the present invention relates to a new planting machine, the special arrangement of which for lifting and carrying the planting units allows to transport assemblies of planting units on said transportation chassis, such that the weight of said assemblies of planting units is evenly distributed upon said chassis, particularly relative to the wheels of said transportation chassis. Moreover, the planting machine of the present invention allows to place assemblies of planting units in a planting position such that said planting units are movable relative to each other in a simple way, as a function of the chosen required planting distance.
2. Description of the Prior Art
As it is known in the art, planting machines have planting units coupled to rolling transportation chassis and arranged in assemblies of planting units covering a width of several meters of the ground to be cultivated. Said covered width is suitable for the planting operation, but is unsuitable for moving said planting machines on roads, highways, as well as for the parking thereof in store houses or for crossing arrow areas.
Two solutions have been implemented in order to solve this drawback caused by the width of said planting machines. On the one hand, planting machines have been developed with planting units, e.g., a total of twelve bodies, that are assembled, in assemblies of four bodies each, i.e., a central assembly and two side assemblies, and said side assemblies are folded over at 90.degree. relative to the central assembly by means of particularly set up gears. The three assemblies of bodies have to be lifted for sufficiently spacing the same from the ground, at a height enough to allow the transportation thereof. Under these conditions, by folding over the side assemblies of said planting units, a decrease in the width of the machine is obtained.
Other planting machines have been developed that are provided with gears for lifting the assemblies of planting units over the related transportation chassis. once lifted, the assemblies are rotated 90.degree. relative to a center line of the machine whereby the planting machine can be moved along narrow roads or can cross narrow areas without drawbacks, because the width of said planting machine is practically given by the total width of the rolling transportation chassis.
Moreover, this type of planting machines have some features that cause additional drawbacks notwithstanding of the solutions found for carrying the planting assemblies on the transportation chassis. Actually, in both the first and second cases mentioned in the prior art, that shall be briefly called "foldable planting machines" and "lifting and rotary planting machines" respectively, in the planting position, the wheels of the transportation chassis and eventually also the planting wheels are interposed between the crop-containing hoppers of the planting units. Under these conditions, in order to change the planting distance, i.e., the distances between furrows, the wheels of the transportation chassis and/or the planting wheels have to be moved, which is an operation that considerably increases the work and the time for getting the planting machine ready. In addition, particularly in the second case of "lifting and rotary planting machines", once the assembly of planting units is lifted and rotated through 90.degree. over the transportation chassis, the weight of said assembly is asymmetrically distributed relative to the wheels of the transportation chassis. As it is apparent, this poor distribution of the load upon the transportation chassis causes unbalancing of said chassis and further unduly overloading of one of the two wheels of the chassis. This asymmetrical load is due to the fact that the lifting of the assembly of planting units is done along a vertical axis symmetrically located relative to the extension of the planting assemblies, but not relative to the distribution of the weight of said assemblies.
While some lifting and rotation machines have been manufactured in order to make the center of gravity of the carrier chassis for the planting units coincide with the center of gravity of the transportation chassis, the effect of coincidence of the centers of gravity is useful at the time of transportation, but in the planting position, i.e., with the carrier chassis lowered, the hoppers of the planting units interfere with the wheels of the transportation chassis.
Thus, it would be advantageous to have a system of lifting and transportating planting assemblies whereby in the planting position the planting units do not interfere with the transportation wheels and, in the transportation position, the weight of the chassis with the planting units is evenly distributed on the machine.
It would be therefore desirable to find an original and effective solution to the drawbacks of the prior art planting machines, by simultaneously solving the two above mentioned problems.